What Is Crigler-Najjar Syndrome?

Crigler-Najjar Syndrome is a rare genetic disorder that affects the liver’s ability to break down bilirubin — a yellow substance produced when red blood cells break down. When the liver can’t process bilirubin properly, it builds up in the body and can lead to jaundice (yellowing of the skin and eyes) and potentially dangerous levels of bilirubin in the blood.

This condition is present from birth and is caused by a mutation in the UGT1A1 gene, which is responsible for producing an enzyme that helps remove bilirubin from the body.

Types of Crigler-Najjar Syndrome?

There are two types:

• Type 1 (Severe Form)
  The body produces little to no bilirubin-processing enzyme. Without treatment, bilirubin can accumulate to life-threatening levels, especially in newborns.
• Type 2 (Milder Form)
  Some enzyme activity is present. Bilirubin levels are elevated but usually not as dangerously high. This form responds better to treatment and has a better long-term outlook.

Causes?

Crigler-Najjar Syndrome is an inherited genetic condition, passed down in an autosomal recessive pattern. This means a child needs to inherit the faulty gene from both parents to develop the disorder.

Symptoms?

Symptoms usually appear shortly after birth and may include:

• Persistent jaundice
• Yellowing of the eyes (sclera)
• Fatigue or poor feeding in infants
• Enlarged liver or spleen (in some cases)
• Neurological symptoms (in severe cases) due to bilirubin buildup in the brain, known as kernicterus

Without treatment, high bilirubin levels can cause permanent brain damage, hearing loss, movement disorders, or even death.

Diagnosis?

Crigler-Najjar Syndrome is typically diagnosed in infancy through:

• Blood tests to check bilirubin levels
• Genetic testing to identify mutations in the UGT1A1 gene
• Liver biopsy or enzyme activity tests (in some cases)

Doctors may also rule out other causes of jaundice in newborns.

Treatment?

Treatment varies depending on the type:

For Type 1:

• Phototherapy
  Blue light therapy helps break down bilirubin in the skin. It’s typically needed for many hours each day, especially in early life.
• Liver transplant
  This may be the only long-term cure, especially when phototherapy becomes less effective with age.
• Calcium compounds or bilirubin binders (experimental therapies) may help in some cases.

For Type 2:

• Phenobarbital (a medication)
  This can help lower bilirubin levels by increasing enzyme activity.
• Regular monitoring
  Bilirubin levels are checked routinely to prevent complications.

Prognosis?

• Type 1 has a serious prognosis if not treated. Without phototherapy or liver transplant, infants are at high risk of severe brain damage or death.
• Type 2 has a much better outlook, especially with medication and regular follow-up. Most people with type 2 live normal or near-normal lives.

Living With Crigler-Najjar Syndrome?

• Infants and children may need daily phototherapy for years.
• Parents must be watchful for signs of increasing jaundice or neurological symptoms.
• Families may require support managing treatment schedules, travel for medical care, and emotional stress.